The wheelchair has seen many iterations over the years, but thanks to innovators, its users can freely move around, allowing them access day-to-day mobility and physical activity.

The first known wheelchair, according to Ability Tool, was purposefully designed for disability and mobility and was called an "invalid’s chair”.

It was invented in 1595 specifically for King Phillip II of Spain. The chair had small wheels attached to the end of a chair’s legs and it included a platform for Phillip’s legs and an adjustable backrest.

It could not be self-propelled, but most likely the King always had servants moving him around.

In 1783, John Dawson of Bath, England invented a wheelchair and named it after his town. The Bath wheelchair had two large wheels in the back and one small one in the front.

The user would steer the chair by a stiff handle, but all the Bath designs had to be pushed or pulled by a donkey or horse, as they were heavy.

The Bath wheelchair did outsell all other models of wheelchairs for 40 years.

Skipping forward to 1655, Steven Farffler, a young German watchmaker with a disability that limited his mobility invented a wheelchair that could be independently propelled.

It was a stable chair mounted on a three-wheeled chassis with attached handles on both sides of the front wheel used to propel the chair forward.

Mr. Farffler, who is believed to have had paraplegia, created the wheelchair himself when he was only 22 years old.

According to Britannica, one of the most-pivotal advances in wheelchair technology in the 20th Century was the invention of the folding wheelchair, initially made with tubular steel, which allowed disabled individuals to use their wheelchairs outside their homes or care facilities.

The first folding designs and tubular-steel chairs were developed within the first decade of the century.

Later, in 1932, disabled American mining engineer Herbert A. Everest and American mechanical engineer Harry C. Jennings introduced the cross-frame wheelchair, which became the standard design for tubular-steel folding chairs.

The two men later formed Everest & Jennings, Inc., which became a leading manufacturer of wheelchairs.

Electric-powered wheelchairs were soon invented by George Klein and others to assist injured veterans after WWII.

Designs from then have since consistently improved in size, weight and to adapt to an individual’s needs.

They are even currently developing a new "iBot type chair" (the former iBot chair is currently discontinued and was extremely expensive) that can rise up on to two wheels, walk up and down stairs, traverse sand, gravel and water and cannot be easily flipped over.

Some speculate that in the future wheelchairs will be able to be controlled by neurological impulses from the brain.